It's not easy being a colossally successful social network. This might sound like sarcasm, but it's not; it's hard to formulate rules that allow 845 million users to express themselves without offering grievous offence, while taking account of laws in scores of jurisdictions. Unsurprisingly, then, recently leaked documents that appear to reveal Facebook's "image and post approval system" have provoked some hostile responses. If your moderation policy doesn't leave anyone feeling as though their freedom of expression has been curtailed just a little, then either it's a bit useless, or you're an admin on 4chan.

… but this one wouldn't Photograph: Jaime Reina/AFP/Getty Images

All of which is a way of paraphrasing Monica Geller: rules are good. Rules help control the fun. You want to proscribe images of child sexual abuse? Everyone can get with that. You want to ban "slurs or racial comments of any kind"? Most people will understand the motivation. You want to ban images of ear wax? I'm not really sure why, to be honest, but I guess we can all get through the day without seeing Uncle Ray's collection of things he has found in his ears.

But I do want to emit a high-pitched whining noise about at least one item on this modern equivalent of the Papal Index. Because right there, sandwiched between "depiction of sexual assault or rape" and "bestiality, necrophilia and pedophilia" is "breastfeeding photos showing other nudity, or nipple clearly exposed".

It might be helpful to be clear here: breastfeeding is – at a basic level – an activity that requires the exposure of the nipple. Some mothers prioritise "discretion", a preoccupation that results in (among other things) Hooter Hiders. Good for them; if it helps them to breastfeed, I'm all for it. But many others find it impossible to breastfeed without displaying some flesh. The wearying insistence on the obscenity of ordinary lactation contributes strongly to a real-world culture in which breastfeeding, despite a thousand officially sanctioned leaflets and posters, is holed below the waterline. Healthcare professionals tell mothers that they simply must breastfeed; yet the public seems to add, "but we must never be aware of it". A society that is not prepared to accept the odd flash of nipple is a society that is not prepared to accept breastfeeding.

And it matters what Facebook does about this, just as its attitude towards "rape lol" culture matters. My reference to the Papal Index isn't entirely facetious; Facebook is one of the most influential cultural mediators in the world. In reflecting and promoting the belief that milky nipples are injurious to public morality, it gives succour to every shopping centre security guard who's ever told a nursing mother to put it away or leave the premises. A mother who is told by Facebook that her breastfeeding photos have been removed because her nipples were showing is quite likely to be humiliated, upset and one step closer to giving up on breastfeeding.

With this in mind, the Guardian has decided to try a little Facebook-busting. If you'd like to mail your pictures of nipple-accessorised breastfeeding to your.pictures@guardian.co.uk, the fearless folk at Comment is free will post them on the Guardian's Facebook page, and see whether Facebook takes them down. UPDATE: see our latest piece here.